An additional type for the item, typically used for adding more specific types from external vocabularies in microdata syntax. This is a relationship between something and a class that the thing is in. In RDFa syntax, it is better to use the native RDFa syntax - the 'typeof' attribute - for multiple types. Schema.org tools may have only weaker understanding of extra types, in particular those defined externally.

A sub property of description. A short description of the item used to disambiguate from other, similar items. Information from other properties (in particular, name) may be necessary for the description to be useful for disambiguation.

The identifier property represents any kind of identifier for any kind of Thing, such as ISBNs, GTIN codes, UUIDs etc. Schema.org provides dedicated properties for representing many of these, either as textual strings or as URL (URI) links. See background notes for more details.

Associates an Event with a Schedule. There are circumstances where it is preferable to share a schedule for a series of
repeating events rather than data on the individual events themselves. For example, a website or application might prefer to publish a schedule for a weekly
gym class rather than provide data on every event. A schedule could be processed by applications to add forthcoming events to a calendar. An Event that
is associated with a Schedule using this property should not have startDate or endDate properties. These are instead defined within the associated
Schedule, this avoids any ambiguity for clients using the data. The propery might have repeated values to specify different schedules, e.g. for different months
or seasons.